Polycystic ovary syndrome (PCOS) is a term most women have heard but few have had explained to them. It is the most common cause of irregular periods, and because these women typically do not ovulate, is a common cause of infertility.

What Causes PCOS?

Polycystic ovary is a term describing ovaries that have multiple small cysts within them. These cysts are really partially developed follicles (the fluid-filled sac where an egg is developing). In a normally cycling woman, one of these follicles will develop to maturity and eventually ovulate, while the other follicles will typically disappear. The hallmark of polycystic ovaries is the excess androgen (male-type hormones) in the ovary. It may sound strange, but in order for the ovary to make estrogen, it must first make testosterone and then convert that to estrogen. The follicles that are able to convert their testosterone to estrogen the best will grow to ovulation, while those that are unable to become estrogen dominant will stop developing. Women with PCOS produce more than the normal amount of testosterone in the ovaries. As a result, the follicles have a difficult time converting all that testosterone to estrogen, so they do not develop to the point of maturity necessary for ovulation.

The ovary makes progesterone only after ovulation has occurred. As women with PCOS do not ovulate, they do not make progesterone as they should. In the normal situation, menstrual bleeding occurs when the uterine lining (also known as the endometrium), first thickens in response to estrogen. After ovulation occurs, the progesterone that is produced provides a supporting structure to the uterine lining and makes it a much firmer, more compact, endometrium. Once the uterine lining has been exposed to progesterone, it goes through changes that make it dependent on the progesterone. When progesterone is withdrawn, the uterine lining has no choice but to shed. Thus when pregnancy does not occur and estrogen and progesterone levels drop at the end of a cycle, the uterine lining sheds and a woman has her period.

PCOS Signs and Symptoms

When ovulation does not occur, the endometrium is exposed only to estrogen and continues to thicken. It does so, however, without the supporting structure that progesterone supplies. Thus at some point, the uterine lining becomes too thick and fragile to stay attached to the uterine wall and sheds both spontaneously and unpredictably. Thus, women with polycystic ovaries may go several months without any bleeding at all, followed by quite a heavy bleeding in an unpredictable manner.

The second problem we see with polycystic ovaries is that women wishing to become pregnant are unable to do so because they are not releasing an egg every month through ovulation. The third problem commonly seen in polycystic ovary patients is that the high testosterone levels cause side effects such as acne or increased hair growth on the face, back, chest and abdomen.

PCOS Causes Weight Gain

Polycystic ovary syndrome makes it difficult for your body to use the hormone insulin, which is the hormone that helps your body convert sugars and starches from foods into energy. If your body isn't producing enough insulin, these sugars and starches will start building up in your bloodstream which also causes high blood pressure. High insulin levels cause the body to produce another hormone called androgen. High androgen levels lead to acne, hair growth, irregular periods, and weight gain. These are all indirect symptoms of PCOS.

Polycystic Ovarian Syndrome Treatment

While these common problems are not life-threatening, they can be very bothersome for women. Over the years, treatments have been applied to women with polycystic ovaries in order to manage their symptoms. For example, menstrual cycles can be managed by providing progesterone or a birth control pill (which is a conveniently packaged form of progesterone). We can also provide medications to decrease the effect of testosterone on hair follicles and decrease unwanted hair growth. We also have medications that can help women ovulate so we can treat infertility associated with polycystic ovaries.

PCOS and Insulin Resistance

These treatments have been the standard approach for many years as there were thought to be no long-term consequences of polycystic ovaries. That attitude has changed, however, in recent years with the discovery of the relationship between polycystic ovaries and elevated insulin levels. Approximately 60% of women with polycystic ovaries also have insulin resistance. Because their bodies do not utilize insulin properly, they compensate by making more insulin to control their blood sugar levels. One of the effects of having extra insulin around is that it directly stimulates the ovary to produce more testosterone, thus producing the polycystic ovaries. Unfortunately, women with high insulin levels are at much higher risk for developing diabetes during pregnancy or actually becoming diabetics as they become older. The increased insulin and testosterone levels in these women also tend to produce a cholesterol profile that puts them at higher risk for heart disease as they get older. For this reason, we now consider polycystic ovaries a condition that should be treated even if women are not bothered by abnormal hair growth or irregular periods or are not wishing to pursue pregnancy at the moment. Medications such as metformin allow insulin to be utilized more efficiently, thus decreasing the need for the pancreas to make as much.

Since the term polycystic ovaries merely describe the appearance of the ovaries in women with increased androgen production, the first step in addressing polycystic ovaries is a thorough evaluation to determine the cause of the excess androgens. Specific treatments are available to address the symptoms, and many women with PCOS need to receive treatment, as the condition may have a significant impact on their lifespan and general health.